Sacked DJ Tony Blackburn has issued a 48 hour ultimatum to his former boss: Apologise or face a writ for defamation.

The veteran broadcaster - who touched down in St Lucia for a holiday - has sent a formal warning to BBC director general Tony Hall that he will sue unless Lord Hall says sorry over an interview he gave last week.

It followed the release of Dame Janet Smith ’s report into Jimmy Savile when Lord Hall claimed she hadn’t believed some of the evidence given by the 73-year-old radio favourite.

Lord Hall said: “Tony Blackburn was interviewed, according to the records, according to her belief, by two people. Dame Janet rejects his evidence to this inquiry. That’s serious.”

Asked if Blackburn had simply had a lapse of memory, Lord Hall replied: “I would point you to the paragraphs in her report where she says that his solicitor said, ‘You should believe the documents you have in front of you; rather than what my client has said’.”

Now sources close to Mr Blackburn have revealed he has sent a formal defamation warning the Beeb boss he faces court unless he apologises.

The letter says the court action would involve two allegations of defamation regarding Mr Blackburn and his lawyers.

Both Blackburn and his solicitor, Martin Howe, claim they were misrepresented by Hall during interviews on BBC news.

An insider said: “The letter warns that this will go all the way unless Hall apologises by end of play Monday.”

Exhausted: Blackburn arrives in St. Lucia with his wife Debbie (Image: James Breeden/Breeden Media LLC)

Last night a spokesperson for the BBC said: “Clearly Mr Blackburn and the BBC are in disagreement on a range of issues. Our position hasn’t changed. As matters are potentially subject to a legal process, we have nothing further to add at this stage.”

Blackburn has previously described how tragic dancer Claire McAlpine would turn up at his flat and how her death made him fear for his reputation.

He wrote in his 1985 book Tony Blackburn: The Living Legend: “It’s so easy for your reputation to be damaged even if you’re innocent.” He does not refer to Claire, 15, who killed herself in 1971, by name but as “a ‘dolly’ dancer on Top of the Pops”.

The DJ adds: “The girl was a groupie who turned up at my flat on several occasions but I never let her inside. She left a diary claiming she’d had sex with me. Her inquest revealed she lived in a fantasy world.”

Mr Blackburn also describes going into hiding to avoid media scrutiny of his involvement with the teen. He said: “It was an anxious time.”

DJ made Savile joke about 'Young Girl' hit

Tony Blackburn joked off-air that a hit about a man’s love for a child was Jimmy Savile’s favourite song.

The DJ then played Young Girl to his Capital Gold listeners, overlaid with taped sounds of Savile’s moans.

Taboo: Gary Puckett and The Union Gap had a hit with 'Young Girl' (Image: Getty Images)

It happened in 1990 when Blackburn was being interviewed for the Sunday Telegraph. He told the reporter and former Radio 1 DJ David Hamilton: “Jimmy Savile’s favourite record coming up now.”

Asked what it was, Blackburn said it was Young Girl by Gary Puckett and The Union Gap. Hamilton said: “You can’t do that joke on the air.” Blackburn is quoted as saying: “Oh yes I can.”